16 research outputs found

    ANÁLISIS, DISEÑO E IMPLEMENTACIÓN DE UN CONVERTIDOR ĆUK PARA ILUMINACIÓN LED

    Get PDF
    El presente artículo describe el análisis, diseño, implementación y resultados experimentales de un convertidor Ćuk cómo fuente de alimentación para un luminario LED. Para el análisis del convertidor se utilizó el modelado mediante espacio de estados, a través del cual se determinó la solución en estado estable y las funciones de transferencia necesarias para cerrar el lazo de control. El convertidor implementado opera en modo de conducción continua (MCC) cuyo voltaje de salida son 68 V y una corriente de 0.88 A para manejar el luminario comercial de 60 W

    IMPLEMENTACIÓN DE LA TÉCNICA ESCALAR SPWM EN UN SISTEMA DE BAJO COSTO

    Get PDF
    En este artículo se presenta la implementación de la técnica de modulación escalar SPWM en un sistema de bajo costo. El hardware desarrollado se compone de un PIC16F1938, tres drivers IR2302, una pantalla LCD Nokia 5110 y cinco botones empleados en la interfaz de usuario. Para la validación del sistema se realizaron pruebas a lazo abierto con un motor de inducción jaula de ardilla de 4 polos de 0.2 kW conectado a un módulo inversor trifásico LabVolt. Así mismo, el sistema cuenta con una interfaz gráfica amigable al usuario que le permite modificar parámetros tales como: frecuencia, sentido de giro y habilitar o deshabilitar señales de control. El sistema desarrollado a su vez, puede ser utilizado para implementar otras técnicas de modulación de manera sencilla y económica

    Desarrollo de una práctica de Estadística Descriptiva con GeoGebra

    Get PDF
    El presente trabajo pretende dar una pauta para emplear el potencial de las herramientas TIC con el propósito de facilitar en el aula y fuera de ella, el aprendizaje de conceptos propios de la estadística a un nivel universitario. Existen diversos programas computacionales capaces de realizar análisis estadísticos de alto nivel: SPSS, Minitab, Matlab, por mencionar algunos; estos programas funcionan muy bien cuando se trata de encontrar respuestas a planteamientos complicados o cuando se tiene un enorme banco de datos. Para emplear de la forma correcta este tipo de software y no malinterpretar sus resultados, es necesario en primer lugar, que el usuario entienda perfectamente los conceptos básicos de la estadística descriptiva, como son el análisis para datos agrupados y no agrupados, medidas de tendencia central y de dispersión, así como los diversos gráficos y tablas de datos que describen la frecuencia con la cual sucede un evento; para lo cual es necesario el uso de un software dinámico y en este caso diseñado específicamente para el aprendizaje didáctico de las matemáticas como lo es GeoGebra

    Adelante / Endavant

    Get PDF
    Séptimo desafío por la erradicación de la violencia contra las mujeres del Institut Universitari d’Estudis Feministes i de Gènere "Purificación Escribano" de la Universitat Jaume

    Atypical Parathyroid Adenoma Complicated with Protracted Hungry Bone Syndrome after Surgery: A Case Report and Literature Review

    No full text
    Hungry Bone Syndrome refers to the severe and prolonged hypocalcemia and hypophosphatemia, following parathyroidectomy in patients with hyperparathyroidism. We present the case of an eighteen-year-old woman with a four-year history of hyporexia, polydipsia, weight loss, growth retardation, and poor academic performance. The diagnostic work-up demonstrated primary hyperparathyroidism with hypercalcemia of 13.36 mg/dL, a PTH level of 2551 pg/mL, bone brown tumors, and microcalcifications within pancreas and kidneys. Neck ultrasonography revealed a parathyroid adenoma of 33 × 14 × 14 mm, also identified on 99Tc-sestamibi scan. Bone densitometry showed decreased Z-Score values (total lumbar Z-Score of −4.2). A right hemithyroidectomy and right lower parathyroidectomy were performed. Pathological examination showed an atypical parathyroid adenoma, of 3.8 g of weight and 2.8 cm in diameter. After surgery she developed hypocalcemia with tetany and QTc interval prolongation. The patient required 3 months of oral and intravenous calcium supplementation due to Hungry Bone Syndrome (HBS). After 42 months, she is still under oral calcium. Usually HBS lasts less than 12 months. Therefore we propose the term “Protracted HBS” in patients with particularly long recovery of 1 year. We present a literature review of the diagnosis, pathophysiology, and treatment of HBS

    Tendencias en la circulación, experiencias y resignificaciones de la migración y el retorno en el Estado de Méxíco

    No full text
    Para abonar al estudio de las migraciones entre México y Estados Unidos y en especial de las migraciones y los migrantes desde el Estrado de México, el libro Continuidades y Cambios en las Migraciones de México a Estados Unidos. Tendencia en la circulación, experiencia y significaciones de la migración y el retorno en el ]Estado de México compila un total de 16 Capítulos que con diferentes acercamientos posicionamientos teóricos y metodologías basadas en estudios de caso y análisis cuantitativo y cualitativo exponen diversas temáticas que revisten la complejidad que ha adquirido el fenómeno migratorio. También exponen la migración internacional desde el Estado de México, entidad que además de constituirse como un Territorio expulsor de migrantes internacionales, ha incrementado su importancia como receptor de migrantes de retorno(no necesariamente originarios del Estado de México) y migrantes en transito que buscan llegar al vecino país del norte

    A Higher Fructose Intake Is Associated with Greater Albuminuria in Subjects with Type 2 Diabetes Mellitus

    No full text
    The aim of this single center cross-sectional study was to investigate the association between fructose intake and albuminuria in subjects with type 2 diabetes mellitus (T2DM). This is a single center cross-sectional study. One hundred and forty-three subjects with T2DM were recruited from the Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran. The median daily fructose intake was estimated with a prospective food registry during 3 days (2 week-days and one weekend day) and they were divided into low fructose intake (<25 g/day) and high fructose intake (≥ 25 g/day). Complete clinical and biochemical evaluations were performed, including anthropometric variables and a 24-hour urine collection for albuminuria determination. One hundred and thirty-six subjects were analyzed in this study. We found a positive significant association between daily fructose intake and albuminuria (ρ= 0.178, p=0.038) in subjects with type 2 diabetes mellitus. Other variables significantly associated with albuminuria were body mass index (BMI) (ρ= 0.170, p=0.048), mean arterial pressure (MAP) (ρ= 0.280, p=0.001), glycated hemoglobin (A1c) (ρ= 0.197, p=0.022), and triglycerides (ρ= 0.219, p=0.010). After adjustment for confounding variables we found a significant and independent association between fructose intake and albuminuria (β= 13.96, p=0.006). We found a statistically significant higher albuminuria (60.8 [12.8-228.5] versus 232.2 [27.2-1273.0] mg/day, p 0.002), glycated hemoglobin (8.6±1.61 versus 9.6±2.1 %), p= 0.003, and uric acid (6.27±1.8 versus 7.2±1.5 mg/dL), p=0.012, in the group of high fructose intake versus the group with low fructose intake, and a statistically significant lower creatinine clearance (76.5±30.98 mL/min versus 94.9±36.8, p=0.014) in the group with high fructose intake versus the group with low fructose intake. In summary we found that a higher fructose intake is associated with greater albuminuria in subjects with T2DM

    Towards a Change in the Diagnostic Algorithm of Autism Spectrum Disorders: Evidence Supporting Whole Exome Sequencing as a First-Tier Test

    No full text
    Autism spectrum disorder (ASD) is a prevalent and extremely heterogeneous neurodevelopmental disorder (NDD) with a strong genetic component. In recent years, the clinical relevance of de novo mutations to the aetiology of ASD has been demonstrated. Current guidelines recommend chromosomal microarray (CMA) and a FMR1 testing as first-tier tests, but there is increasing evidence that support the use of NGS for the diagnosis of NDDs. Specifically in ASD, it has not been extensively evaluated and, thus, we performed and compared the clinical utility of CMA, FMR1 testing, and/or whole exome sequencing (WES) in a cohort of 343 ASD patients. We achieved a global diagnostic rate of 12.8% (44/343), the majority of them being characterised by WES (33/44; 75%) compared to CMA (9/44; 20.4%) or FMR1 testing (2/44; 4.5%). Taking into account the age at which genetic testing was carried out, we identified a causal genetic alteration in 22.5% (37/164) of patients over 5 years old, but only in 3.9% (7/179) of patients under this age. Our data evidence the higher diagnostic power of WES compared to CMA in the study of ASD and support the implementation of WES as a first-tier test for the genetic diagnosis of this disorder, when there is no suspicion of fragile X syndrome

    COVID-19 in hospitalized HIV-positive and HIV-negative patients : A matched study

    Get PDF
    CatedresObjectives: We compared the characteristics and clinical outcomes of hospitalized individuals with COVID-19 with [people with HIV (PWH)] and without (non-PWH) HIV co-infection in Spain during the first wave of the pandemic. Methods: This was a retrospective matched cohort study. People with HIV were identified by reviewing clinical records and laboratory registries of 10 922 patients in active-follow-up within the Spanish HIV Research Network (CoRIS) up to 30 June 2020. Each hospitalized PWH was matched with five non-PWH of the same age and sex randomly selected from COVID-19@Spain, a multicentre cohort of 4035 patients hospitalized with confirmed COVID-19. The main outcome was all-cause in-hospital mortality. Results: Forty-five PWH with PCR-confirmed COVID-19 were identified in CoRIS, 21 of whom were hospitalized. A total of 105 age/sex-matched controls were selected from the COVID-19@Spain cohort. The median age in both groups was 53 (Q1-Q3, 46-56) years, and 90.5% were men. In PWH, 19.1% were injecting drug users, 95.2% were on antiretroviral therapy, 94.4% had HIV-RNA < 50 copies/mL, and the median (Q1-Q3) CD4 count was 595 (349-798) cells/μL. No statistically significant differences were found between PWH and non-PWH in number of comorbidities, presenting signs and symptoms, laboratory parameters, radiology findings and severity scores on admission. Corticosteroids were administered to 33.3% and 27.4% of PWH and non-PWH, respectively (P = 0.580). Deaths during admission were documented in two (9.5%) PWH and 12 (11.4%) non-PWH (P = 0.800). Conclusions: Our findings suggest that well-controlled HIV infection does not modify the clinical presentation or worsen clinical outcomes of COVID-19 hospitalization

    How do women living with HIV experience menopause? Menopausal symptoms, anxiety and depression according to reproductive age in a multicenter cohort

    Get PDF
    CatedresBackground: To estimate the prevalence and severity of menopausal symptoms and anxiety/depression and to assess the differences according to menopausal status among women living with HIV aged 45-60 years from the cohort of Spanish HIV/AIDS Research Network (CoRIS). Methods: Women were interviewed by phone between September 2017 and December 2018 to determine whether they had experienced menopausal symptoms and anxiety/depression. The Menopause Rating Scale was used to evaluate the prevalence and severity of symptoms related to menopause in three subscales: somatic, psychologic and urogenital; and the 4-item Patient Health Questionnaire was used for anxiety/depression. Logistic regression models were used to estimate odds ratios (ORs) of association between menopausal status, and other potential risk factors, the presence and severity of somatic, psychological and urogenital symptoms and of anxiety/depression. Results: Of 251 women included, 137 (54.6%) were post-, 70 (27.9%) peri- and 44 (17.5%) pre-menopausal, respectively. Median age of onset menopause was 48 years (IQR 45-50). The proportions of pre-, peri- and post-menopausal women who had experienced any menopausal symptoms were 45.5%, 60.0% and 66.4%, respectively. Both peri- and post-menopause were associated with a higher likelihood of having somatic symptoms (aOR 3.01; 95% CI 1.38-6.55 and 2.63; 1.44-4.81, respectively), while post-menopause increased the likelihood of having psychological (2.16; 1.13-4.14) and urogenital symptoms (2.54; 1.42-4.85). By other hand, post-menopausal women had a statistically significant five-fold increase in the likelihood of presenting severe urogenital symptoms than pre-menopausal women (4.90; 1.74-13.84). No significant differences by menopausal status were found for anxiety/depression. Joint/muscle problems, exhaustion and sleeping disorders were the most commonly reported symptoms among all women. Differences in the prevalences of vaginal dryness (p = 0.002), joint/muscle complaints (p = 0.032), and sweating/flush (p = 0.032) were found among the three groups. Conclusions: Women living with HIV experienced a wide variety of menopausal symptoms, some of them initiated before women had any menstrual irregularity. We found a higher likelihood of somatic symptoms in peri- and post-menopausal women, while a higher likelihood of psychological and urogenital symptoms was found in post-menopausal women. Most somatic symptoms were of low or moderate severity, probably due to the good clinical and immunological situation of these women
    corecore